An electronic assembly typically includes a printed circuit board having a relatively large number of electronic components mounted thereon. The electronic components of the assembly may take on a variety of different shapes and sizes and may be mounted to the circuit board in a variety of different ways. For example, complex integrated circuit packages may be die mounted onto the board using a ball-grid array, whereas mechanical connectors and the like may be mounted by use of through hole leads. Other components such as SOIC's, SOT's, and surface mounted resistors and capacitors may be surface mounted on the top or bottom side of the board and soldered using either reflow or wave soldering techniques.
The layout and design of electronic assemblies can be a relatively complex task. Indeed, designers are often faced with problems such as insufficient board “real estate,” conflicts with design standards, product cost constraints, etcetera. For example, during the layout and design of an assembly, the designer may run out of room for the components to be mounted on the topside board, yet the designer does not have all of the parts placed on the topside of the board. Moreover, the current design guidelines under which the designer is operating may state that, for example, surface mounted chips are not to be placed on the bottom side of the board. Hence, the designer is faced with the choice of either (1) putting surface mounted chips on the bottom side thereby violating the design guidelines in addition to increasing the cost of the assembly, (2) increasing the size of the board thereby increasing its cost, or (3) increasing the “technology level” of the assembly with smaller components thereby also increasing the cost of the assembly.
In light of the fact that each of the above-identified options increases the cost of the assembly, the designer must determine which of the options will yield the most cost effective solution to the problem. In other words, the designer is challenged with finding the solution to his or her problem that increases the cost of the assembly by the least amount. In reality, of course, there is no universal solution to such a problem. Each situation is generally unique. In practice, the typical way to explore the designer's options is to have a circuit board vendor and an assembler quote each different option and then compare them. Unfortunately, getting these vendors to allow access to quoting resources with no prospect for an order is often difficult. There is no way the designer can do this for herself or himself.
Hence, the designer often takes her or his “best guess” at a solution to the design dilemma. The design is then presented to a supply base of vendors to determine the cost of the product based on the design. Often the “real” cost of the product based on the design exceeds the marketing expectations resulting in costly redesign efforts to reduce the cost.